@stevebrockie3 

Hi,

We had a Vaillant ASHP 12kw fitted last October. We have a big old drafty cottage on the Yorkshire coast and had no choice but to install before we could do any other work. The majority of the house cant be insulated as its chalk,cobble, mud etc with no cavity only in a later extension. We have the whole pipework replaced and triple rads fitted. It worked lovely in the winter reaching 20degrees which was sufficient however it was costing about £300pm! Once we realised we lowered the heat and turned some rads right down. It also cut out in -2 temp, but they claim thats because it needs a bigger cable (we had problems with the fitters you can see on another thread).

I now take the meter reading everyday to check and we use about 5 units a day at the moment in total (not just hot water), we have had new windows and doors fitted and kingspan on many of the internal walls. More to do, but expecting it to perform much better this winter.

Look us up on facebook 'bramley manor cottage' and you'll see if the size is comparable to yours.

We need solar panels but neighbours are whinging about everything so far and we are running out of money so not sure when that will happen but id imagine it would then be really economical.

Good Luck

@stevebrockie3, If your installers are MCS certified, they have to do a room, by room calculation that takes your current build, insulation levels, ventilation and room temperatures (21 in the living areas and 18 in the bedrooms) in to account. Ask them for this, they have to give it to you with your quotation and with this there should be a radiator schedule for every room. In addition to this, ask the installer for manufacturer's evidence that the chosen heat pump will supply the required heat at the design temperature or duty point (usually between -1 and -5 depending on latitude and altitude). They should also be able to supply you with performance and running cost estimates, do not be afraid to interrogate these thoroughly, good installers will welcome it. If the installer struggles with this, get another installer.

If your installer is not MCS certified, get another one that is, as you will not be able to claim the RHI grant.

@stevebrockie3, did you end up committing to an air source heat pump?

@editor hi Mars, no we didn’t in the end. We’ve decided to grin and bear the extortionate LPG costs for another winter then will look into Biomass in the spring. Meanwhile we’re replacing all the windows and beefing up the loft/eaves insulation and will put in composite front/back doors as the old timber doors have to be a major contributing factor to the heat loss.